Composite materials (made of fibers in a resin matrix) are light weight but strong and thus are widely used in a variety of applications. Composites, however, are typically non-conductive which can be problematic when structures made from composite materials must be grounded or protected against electromagnetic interference, lightning, or the like.
So, those skilled in the art in composite technology may incorporate a conductive metal mesh layer into the composite ply lay-up. During curing of the lay-up, however, the composite resin infiltrates the metal mesh material rendering it non-conductive. Attempts at removing the resin from the metal mesh by abrasion (e.g., grit blasting or sanding operations) are less than satisfactory. The result was often a non-uniform surface, incomplete removal of the resin, and removal of or damage to the metal mesh material. Attempts to use peel plies in the composite lay-up in the area that was required to be resin free were also less than satisfactory since resin often still coated the metallic mesh material.